Combined iterative cross-correlation demodulation scheme for mixing space borne automatic identification system signals
来源期刊：中南大学学报(英文版)2013年第3期
论文作者：ZHU Shou-zhong(朱守中) WANG Xiao-ling(王小玲) JIANG Wen-li(姜文利) ZHANG Xi-xiang(张锡祥)
文章页码：670 - 677
Key words：space borne automatic identification system; combined iterative cross-correlation demodulation scheme; bit error rate; simulation
Abstract: Aiming at the potential presence of mixing automatic identification system (AIS) signals, a new demodulation scheme was proposed for separating other interfering signals in satellite systems. The combined iterative cross-correlation demodulation scheme, referred to as CICCD, yielded a set of single short signals based on the prior information of AIS, after the frequency, code rate and modulation index were estimated. It demodulates the corresponding short codes according to the maximum peak of cross-correlation, which is simple and easy to implement. Numerical simulations show that the bit error rate of proposed algorithm improves by about 40% compared with existing ones, and about 3 dB beyond the standard AIS receiver. In addition, the proposed demodulation scheme shows the satisfying performance and engineering value in mixing AIS environment and can also perform well in low signal-to-noise conditions.
ZHU Shou-zhong(朱守中)1, WANG Xiao-ling(王小玲)2, JIANG Wen-li(姜文利)1, ZHANG Xi-xiang(张锡祥)1
(1. School of Electronic Science and Engineering,
National University of Defense Technology, Changsha 410073, China；
2. School of Information Science and Engineering, Central South University, Changsha 410083, China)
Abstract:Aiming at the potential presence of mixing automatic identification system (AIS) signals, a new demodulation scheme was proposed for separating other interfering signals in satellite systems. The combined iterative cross-correlation demodulation scheme, referred to as CICCD, yielded a set of single short signals based on the prior information of AIS, after the frequency, code rate and modulation index were estimated. It demodulates the corresponding short codes according to the maximum peak of cross-correlation, which is simple and easy to implement. Numerical simulations show that the bit error rate of proposed algorithm improves by about 40% compared with existing ones, and about 3 dB beyond the standard AIS receiver. In addition, the proposed demodulation scheme shows the satisfying performance and engineering value in mixing AIS environment and can also perform well in low signal-to-noise conditions.
Key words:space borne automatic identification system; combined iterative cross-correlation demodulation scheme; bit error rate; simulation
